Frisk's dog
by MonkeyGirl13
Summary: When Frisk falls down so does her loyal pet dog. How will this change the story and is her dog everything she seems to be? I do not own Undertale only my oc
1. Chapter 1

**I do not own Undertale only my OC**

It was a sunny day on the surface a young Frisk was laying in their bed when a young women walked in with a large German shepherd behind her. The German shepherd was light brown with black patches on its body and its eye. The dog jumped on top of Frisk and licked her face waking her up after getting pushed back Frisk's mother turned to her saying.

"come on Frisk you need to wake up for school" Frisk got their striped purple and blue shirt on and some black pants they then turned to the dog stroking its head.

"good girl Nightshade, now let's go to school" Frisk grabbed their backpack and ran to the door, pulling it open Nightshade ran after Frisk and ran alongside her as they ran to the school gates. When Frisk got to the gates she turned to Nightshade petting their head and going into their bag pulling out a large bone which they through to Nightshade who caught the bone and began to chew on it laying down in the sun. A few hours went by and Frisk emerged from the school and went to Nightshade. "hey girl where's mum at?" The response to this was a small whine and a tilt of her head. The duo waited a few hours until Frisk decided to walk back home when they got their Frisk noticed how her mums car wasn't there turning to Nightshade Frisk said. "Nightshade go 'round the back" Nightshade barked and ran into the back garden. Frisk opened the front door and saw her dad in the recliner in front of a static TV.

"It's your fault" The dad didn't move he just sat there.

"Dad what are you talking about?" he lunged out and grabbed Frisk pinning her to the wall.

"your mothers dead! And its because of you!"

"what?!"

"she was on her way to pick your ungrateful ass from school. Now your gonna pay" his grip tightened when Nightshade suddenly lunged biting into his arm and throwing him to the ground. The man held his now bleeding arm and screaming in pain Nightshade went to Frisk and pushed her nose into her side and pushed her up. Frisk got up and ran with Nightshade to a hole in the wire fence Frisk ran though the hole followed by Nightshade. As they run with the wilderness they hear the dad chasing after them when suddenly Frisk tripped and fell into a hole when Nightshade caught her on the collar of her jumper. Frisk hung precariously over the hole and the dad was gaining on them. From behind the dad pointed a gun towards Nightshade and fired the bullet skimmed her leg making her stumble forward and let go of Frisk. They had both fallen into the Underground where all of the monsters lived and boy were they in for an adventure.


	2. Chapter 2

Frisk woke up after several hours she looked up and saw that she had fallen into the Underground next to her lay Nightshade Frisk stroked her head, waking her up. They sat there for a few minutes Frisk hugging Night when suddenly a high pitched voice broke through the darkness.

"Howdy I'm Flowey, Flowey the flower" Night' walked towards Flowey and sniffed at it. "hehehe hey there pooch" Night' suddenly began growling but Frisk pulled her back by the scruff of her neck yet even then Nightshade would still growl quietly at the odd little flower. "welcome to the Underground you must have heard some stories about this place but don't worry this place is actually very nice" the golden flower smiled and continued. "since no one is around looks like little old me will have to teach you how things work down here" Severeal sharp pellets floated around Flowey's head. "these are called **Freindliness pellets** these will help increase your **LV**. Whats LV? why it stands for LOVE, silly. You need to catch all these to get your LV up, go on catch as many as you can" the pellets zoomed at Frisk and her canine companion but as the pellets hit Frisk they cut her skin and stabbed into her. Nightshade saw this and began barking and growling at Flowey who was now laughing manicly. Nightshade charged at Flowey and bared her teeth but as she got closer Flowey fired more pellets which hit her directly flinging her into Frisk who fell to the floor with 'Night on top of her. "you idiot's in this world it's kill or be killed!" he then let out a blood-curdeling laugh and enclosed the two with more pellets that began to move towards them. However before they could kill the two a fireball hit Flowey flinging him away where he had just been stood a tall female goat monster who was wearing a long purple dress with a symbol on it.

"what a miserable creature torturing such an innocent youth" the goat women turned to the two and said. "don't worry my child my name is Toriel, caretaker of the ruins" Nightshade barked happily and ran to Toriel sitting in front of her, Toriel smiled and storked the dogs head this made Frisk walk foreward smiling. "now follow me my child my home is close by" the two left following close to Toriel. They soon came to a door with a switch Toriel stopped in front of the switch. "in the ruins there are many puzzels that you will need to solve to get though. Most work like this puzzle" Toriel then flipped a switch that opened a doorway. After a few hours of walking later Toriel had taught the two about the monsters and how they could spare them by making them happy enough to not wanting to fight. Soon after this Toriel had, had to leave the two to go and take care of something but when she left Frisk and Nightshade had left the room and advanced to the other rooms finding more puzzles and monsters. Throughout the puzzles Toriel would call asking about Cinnimon or Butterscotch but when they got to one room Frisk stops and looks at the phone that Toriel had given her. Nightshade looks back and see's Frisk fiddeling with the phone before nudging thier nose into their stomach. Frisk smiles and sits down next to the dog again looking at the phone.

"I want to ask her to be my mum" even though 'Night is a dog even she seemed shocked at what Frisk just said. "she is kind to me and she treats me like her daughter" 'Night nudged the phone before happily barking this made Frisk smile before dialing Toriel. "hey Toriel I was wondering if I could possibly call you mom?"

 _"well this certainly is quite a surprise but if that is what will make you happy then very well my child. You may call me your mom if you wish"_ Frisk smiled and ended the call placing it back in her backpack. After a few more rooms they came to a room with a large back tree that had red fallen trees around the bottom of it. This was when Toriel came around the corner she pulled out her phone and dialed Frisks phone rang and that was when Toriel saw the two in the same room. "My child I can not believe that you managed to get here without a single scratch. Even still it was a bad decision to leave you all alone even if you had your dog with you" Toriel looked away but looked back saying. "anyway let us go to my house then" Toriel took Frisk's hand and walked to a cozy house only a few minutes away. Frisk and Nightshade walked through and decided to go to their room when they got in they found a bed already made. Frisk yawned and stretched as she climbed into bed Nightshade yawned herself and jumped onto the foot of the bed where she curled up and fell asleep. A few hours later both Frisk and Nightshade woke up and on the floor sat two plates of Butterscotch pie. Frisk picked up the two plates and placed them in her backpack and walked out with Nightshade to the living room where Toriel was sat in a large reading chair in front of a burning fireplace reading a book. "hello my child I was wondering when you would wake up"

"mum I was wondering how do I exit the ruins to get back to the surface?" 'Night looked up at Frisk who simply placed a hand on the dog's head.

"my child what do you mean? T-this is your home now. W-would you like to hear about this book that I am reading?" Frisk simply looked sternly at Toriel.

"please can you tell me how to exit the ruins" Toriel suddenly stood up placing her book down and says.

"please excuse me my child there is something I must do please stay here" With that Toriel left the room however Frisk followed quickly behind her along with Nightshade. They followed after her down a set of long steps which led to a long corridor where Toriel stood. "you really want to leave so badly? I've seen what happens multiple times they come, they leave, they die. Please be a good child and go back upstairs" Toriel then keeps on going down the hallways as Frisk and 'Night follow afterwards they come to a large door with Toriel stood in front of it. "I won't let another one die if you really want to leave so badly prove to me that you have what it takes to survive out there" Suddenly Toriel fires multiple fireballs towards the two. Nightshade jumped to the side as a fireball lands on the ground. After several attacks Toriel lowers her hands in defeat. "It is funny I can't even save the life of one child" Toriel then kneels down and places one hand on Frisk's shoulder as she says. "beyond this door is a long corridor once you go through there that will be the way to exit the ruins fully. When you leave please do not come back I hope you understand" tears begin to form in Frisk's eyes she suddenly wrpas her arms around Toriel and gives her a hug. When Toriel leaves the two go through the door and find a large room with a small patch of grass where suddenly a yellow flower springs up from the ground. Nightshde growls at Flowey as he laughs.

"Don't you get it so what you saved the life of one monster in the end you will want to kill someone who will annoy you. But don't worry I won't kill you yet I have much bigger plans for you and your mutt. See ya later!" With that Flowey burrowed back into the ground and dissapered. The two looked at each other and carried on walking. They soon came to a second large door which they opened reaviling a large snowy forest beyond the door.


End file.
